Plasma tryptophan pathway metabolites quantified by liquid chromatography-tandem mass spectrometry as biomarkers in neuroendocrine tumor patients

A good and accessible biomarker is of great clinical value in neuroendocrine tumor (NET) patients, especially considering its frequently indolent nature and long-term follow-up. Plasma chromogranin A (CgA) and 5-hydroxyindoleacetic acid (5-HIAA) are currently used as biomarkers in NET, but their sensitivity and specificity are restricted. 5-HIAA is the main metabolite of serotonin, an important neurotransmitter of the tryptophan pathway. The aim of this study is to estabish a sensitive and accurate method for the quantification of tryptophan pathway metabolites in plasma. We further aimed to evaluate its utility as a clinical tool in NET disease. We obtained plasma samples from NET patients and healthy controls recruited from the University Hospital of North Norway, Tromsø. Samples were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS), and eight metabolites of the tryptophan pathway were quantified. We included 130 NET patients (72/130 small intestinal [SI] NET, 35/130 pancreatic NET, 23/130 other origin) and 20 healthy controls. In the SI-NET group, 26/72 patients presented with symptoms of carcinoid syndrome (CS). We found that combining tryptophan metabolites into a serotonin/kynurenine pathway ratio improved diagnostic sensitivity (92.3%) and specificity (100%) in detecting CS patients from healthy controls compared with plasma 5-HIAA alone (sensitivity 84.6%/specificity 100%). Further, a clinical marker based on the combination of plasma serotonin, 5-HIAA, and 5OH-tryptophan, increased diagnostic capacity identifying NET patients with metastasized disease from healthy controls compared with singular plasma 5-HIAA, serotonin, or CgA. In addition, this marker was positive in 61% of curatively operated SI-NET patients compared with only 10% of healthy controls (p < .001). Our results indicate that simultaneous quantification of several tryptophan metabolites in plasma, using LC-MS/MS, may represent a clinically useful diagnostic tool in NET disease.

Praxis-Informed Pointers: A Student Guide for Optimizing Clinical Learning in a Resource-Constrained Setting

Issue: Health professions education (HPE) is intimately linked with teaching and learning in the clinical environment. While the value of authentic clinical experiences is acknowledged, whether learning actually occurs is to a large extent dependent on students' behaviors and attitudes. The kinds of student behaviors and attitudes that are necessary to optimize learning in the clinical environment thus becomes relevant. Evidence: Tips and recommendations to maximize clinical learning in a variety of settings have been well documented. There is, however, a dearth of literature which takes a narrative-based praxis approach focused on resource-constrained environments. We developed this praxis-orientated article as a means to translate the available literature and theory into a simple, practical guide, focused on optimizing clinical learning from a student perspective, remaining cognizant of the particular challenges present in a resource-constrained setting. Implications: Based on the resource-constrained environments our students are exposed to, we outline the following six key aspects: student-driven learning, integration into the community of practice, student engagement, empathy, interprofessional learning opportunities, and feedback for learning. These aspects provide useful pointers for students in general. Furthermore, exploration into what strategies students may utilize in resource-constrained clinical contexts is addressed.

Congenital hypotonia: systematic approach for prenatal detection

OBJECTIVES

Congenital hypotonic conditions are rare and heterogeneous, and some are severely debilitating or lethal. Contrary to its prominent postnatal manifestation, the prenatal presentation of hypotonia is frequently subtle, inhibiting prenatal detection. We aimed to characterize the prenatal sonographic manifestation of congenital hypotonia throughout pregnancy, evaluate the yield of diagnostic tests and propose diagnostic models to increase its prenatal detection.

METHODS

This was a retrospective observational study of singleton pregnancies with congenital hypotonia, diagnosed either prenatally or immediately after birth, at a single tertiary center between the years 2012 and 2020. Prenatally, hypotonia was diagnosed if a fetus showed sonographic or clinical signs suggestive of hypotonia and had a confirmed underlying genetic condition, or in the absence of a known genetic abnormality if the fetus exhibited multiple prominent signs suggestive of hypotonia. Postnatally, it was diagnosed in neonates displaying reduced muscle tone leading to reduced spontaneous movement, reduced swallowing or feeding difficulty. We reviewed the medical records of pregnant patients carrying fetuses subsequently diagnosed with congenital hypotonia and assessed the yield of ultrasound scans, fetal magnetic resonance imaging, computed tomography and genetic tests. The detection rate of sonographic signs suggesting fetal hypotonia was calculated. The prevalence of non-specific signs, including polyhydramnios, persistent breech presentation, intrauterine growth restriction and maternal perception of reduced fetal movement, were compared between the study group and the local liveborn singleton population. Potential detection rates of different theoretical semiotic diagnostic models, differing in the threshold for referral for a targeted scan, were assessed based on the cohort's data.

RESULTS

The study group comprised 26 cases of congenital hypotonia, of which 10 (38.5%) were diagnosed prenatally, and the controls included 95 105 singleton live births, giving a prevalence of congenital hypotonia of 1:3658. Nuchal translucency thickness and the early anomaly scan at 13-17 weeks were normal in all 22 and 23 cases, respectively, in which this was performed. The mid-trimester scan performed at 19-25 weeks was abnormal in four of 24 (16.7%) cases. The overall prenatal detection rate of congenital hypotonic conditions in our cohort was 38.5%. Only cases which underwent a targeted scan were detected and, among the 16 cases which underwent this scan, the prenatal detection rate was 62.5% compared with 0% in pregnancies that did not undergo this scan (P = 0.003). An abnormal genetic diagnosis was obtained in 21 (80.8%) cases using the following modalities: chromosomal microarray analysis (CMA) in two (9.5%), whole-exome sequencing (WES) in 14 (66.7%) and methylation analysis in five (23.8%). CMA was abnormal in 8% (2/25) of the cases and WES detected a causative genetic mutation in 87.5% (14/16) of the cases in which these were performed. Comparison of non-specific signs in the study group with those in the local singleton population showed that hypotonic fetuses had significantly more polyhydramnios (64.0% vs 3.0%, P < 0.0001), persistent breech presentation (58.3% vs 4.2%, P < 0.0001), intrauterine growth restriction (30.8% vs 3.0%, P < 0.0001) and maternal perception of reduced fetal movement (32.0% vs 4.7%, P < 0.0001). Prenatally, the most commonly detected signs supporting a diagnosis of hypotonia were structural anomaly (62.5%, 10/16), reduced fetal movement (46.7%, 7/15), joint contractures (46.7%, 7/15) and undescended testes ≥ 30 weeks (42.9%, 3/7 males). Proposed diagnostic strategies that involved performing a targeted scan for a single non-specific ultrasound sign or two such signs, and then carrying out a comprehensive genetic evaluation for any additional sign, offered theoretical detection rates in our cohort of 88.5% and 57.7%, respectively.

CONCLUSIONS

Congenital hypotonic conditions are rare and infrequently detected prenatally. Sonographic signs are visible from the late second trimester. A targeted scan increases prenatal detection significantly. Comprehensive genetic testing, especially WES, is the cornerstone of diagnosis in congenital hypotonia. Theoretical diagnostic models which may increase prenatal detection are provided. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

The health economic impact of cow's milk allergy in childhood: A retrospective cohort study

Background

Cow's milk allergy (CMA) is one of the most common food allergies among children. Whilst avoidance of cow's milk protein is the cornerstone of management, further treatment of symptoms including those affecting the gastrointestinal, skin and respiratory systems plus other allergic comorbidities, maybe required. This study aimed to quantify the wider economic impact of CMA and its management in the United Kingdom (UK).

Methods

We conducted a retrospective matched cohort study on children with CMA (diagnosis read code and/or hypoallergenic formula prescription for ≥3 months) examining healthcare data (medication prescriptions and healthcare professional contacts) from case records within The Health Improvement Network (A Cegedim Proprietary Database) in the UK. A comparative cost analysis was calculated based on healthcare tariff and unit costs in the UK.

Results

6998 children (54% male; mean observation period 4.2 years) were included (n = 3499 with CMA, mean age at diagnosis 4.04 months; n = 3499 matched controls without CMA). Compared to those without CMA, medications were prescribed to significantly more children with CMA (p < 0.001) at a higher rate (p < 0.001). Children with CMA also required significantly more healthcare contacts (p < 0.001) at higher rate (p < 0.001) compared to those without CMA. CMA was associated with additional potential healthcare costs of £1381.53 per person per year.

Conclusion

The findings of this large cohort study suggest that CMA and its associated co‐morbidities presents a significant additional healthcare burden with economic impact due to higher prescribing of additional medications. Further research into management approaches that may impact these clinical and economic outcomes of CMA is warranted.

Adnexal torsion recurrence-is the adnexal twist degree a risk factor? A retrospective cohort study

OBJECTIVE

To evaluate whether the adnexal twist degree is related to torsion recurrence and whether there is a dose-dependent correlation.

DESIGN

A retrospective cohort study.

SETTING

Single tertiary medical centre.

POPULATION

The study includes non-pregnant patients operated, for the first time, for adnexal torsion, between 2011 and 2018.

METHODS

Information regarding the degree of adnexal twist was collected from surgical reports. Recurrence was identified using a computerised database and ascertained via telephone with a response rate of 87.2% (253/290).

MAIN OUTCOME MEASURES

Adnexal torsion recurrence rate.

RESULTS

A total of 182 women who had undergone laparoscopic detorsion met the inclusion criteria. Twenty-two had torsion recurrence (12.1%). Adnexal twist degree in the primary event was associated with a higher recurrence risk: 4.3% of women with twist degree ≤360 (n = 3/70), 14.5% of women with twist degree of 361-720 (n = 9/62) and 20% of women with twist degree >720 (n = 10/50) (P = 0.03). The median twist degree was 540 (interquartile range [IQR] 360-855) and 720 (IQR 675-1080) degrees in the control and study groups, respectively (P = 0.005). Additional possibly associated factors for recurrence were evaluated. Age emerged as a possible risk factor, with a median age of 19 years in the recurrence group (IQR 14-27 years) versus 28.5 (IQR 19-36 years) in the non-recurrence group (P < 0.01). Logistic regression analysis revealed that together with age, adnexal twist degree remained significantly associated with torsion recurrence (odds ratio [OR] 1.98, 95% CI 1.09-3.61; P = 0.02).

CONCLUSION

Adnexal twist degree was found to be positively associated with the risk of torsion recurrence.

TWEETABLE ABSTRACT

Adnexal twist degree was found to be positively associated with the risk of torsion recurrence.

German Registry for Cardiac Operations and Interventions in Patients with Congenital Heart Disease: Report 2020-Comprehensive Data from 6 Years of Experience

Background  Based on a quality assurance initiative of the German Society for Thoracic and Cardiovascular Surgery (DGTHG) and the German Society for Pediatric Cardiology and Congenital Heart Defects (DGPK), a voluntary registry was founded for assessment of treatment and outcomes of patients with congenital heart disease in Germany. This evaluation by the German Registry for cardiac operations and interventions in patients with congenital heart disease reports the data and the outcome over a 6-year period in patients undergoing invasive treatment.

Methods  This real-world database collects clinical characteristics, in-hospital complications, and medium-term outcome of patients who underwent cardiac surgical and interventional procedures within the prospective, all-comers registry. Patients were followed-up for up to 90 days.

Results  In the period from 2013 to 2018, a total of 35,730 patients, 39,875 cases, respectively 46,700 procedures were included at up to 31 German institutions. The cases could be subcategorized according to the treatment intention into 21,027 (52.7%) isolated operations, 17,259 (43.3%) isolated interventions, and 1,589 (4.0%) with multiple procedures. Of these, 4,708 (11.8%) were performed in neonates, 10,047 (25.2%) in infants, 19,351 (48.5%) in children of 1 to 18 years, and 5,769 (14.5%) in adults. Also, 15,845 (33.9%) cases could be allocated to so-called index procedures which underwent a more detailed evaluation to enable meaningful comparability. The mean unadjusted in-hospital mortality of all cases in our registry ranged from 0.3% in patients with isolated interventions and 2.0% in patients with surgical procedures up to 9.1% in patients undergoing multiple procedures.

Conclusion  This annually updated registry of both scientific societies represents voluntary public reporting by accumulating actual information for surgical and interventional procedures in patients with congenital heart disease (CHD) in Germany. It describes advancements in cardiac medicine and is a basis for internal and external quality assurance for all participating institutions. In addition, the registry demonstrates that in Germany, both interventional and surgical procedures for treatment of CHD are offered with high medical quality.

Determining individual trajectories of joint space loss: improved statistical methods for monitoring knee osteoarthritis disease progression

OBJECTIVES

Knee osteoarthritis (KOA) progression is frequently monitored by calculating the change in knee joint space width (JSW) measurements. Such differences are small and sensitive to measurement error. We aimed to assess the utility of two alternative statistical modelling methods for monitoring KOA.

MATERIAL AND METHODS

We used JSW on radiographs from both the control arm of the Strontium Ranelate Efficacy in Knee Osteoarthritis trial (SEKOIA), a 3-year multicentre, double-blind, placebo-controlled phase three trial, and the Osteoarthritis Initiative (OAI), an open-access longitudinal dataset from the USA comprising participants followed over 8 years. Individual estimates of annualised change obtained from frequentist linear mixed effect (LME) and Bayesian hierarchical modelling, were compared with annualised crude change, and the association of these parameters with change in WOMAC pain was examined.

RESULTS

Mean annualised JSW changes were comparable for all estimates, a reduction of around 0.14 mm/y in SEKOIA and 0.08 mm/y in OAI. The standard deviation (SD) of change estimates was lower with LME and Bayesian modelling than crude change (SEKOIA SD = 0.12, 0.12 and 0.21 respectively; OAI SD = 0.08, 0.08 and 0.11 respectively). Estimates from LME and Bayesian modelling were statistically significant predictors of change in pain in SEKOIA (LME P-value = 0.04, Bayes P-value = 0.04), while crude change did not predict change in pain (P-value = 0.10).

CONCLUSIONS

Implementation of LME or Bayesian modelling in clinical trials and epidemiological studies, would reduce sample sizes by enabling all study participants to be included in analysis regardless of incomplete follow up, and precision of change estimates would improve. They provide increased power to detect associations with other measures.

The use of extensively hydrolysed and amino acid feeds beyond cow's milk allergy: a national survey

BACKGROUND

Extensively hydrolysed formulas (EHFs) and amino acid formulas (AAFs) with proven hypoallergenicity are used for children suffering from cow's milk allergy, when breast milk is not available. However, these feeds are often used in other medical conditions where tolerance and absorption of whole protein is affected, frequently without assessment of efficacy. This practice survey assessed the use of these feeds in paediatric conditions other than cow's milk allergy; aiming to describe the population, growth parameters and micronutrient status.

METHODS

Four National Health Service tertiary paediatric centres participated in this practice survey. Inclusion: children between 0 and 18 years, consuming >25% of their estimated energy requirements of an EHF/AAF for any condition other than allergic disease. Anonymised data were collected: (i) descriptive information; (ii) indications; (iii) type and route of feeding; (iv) growth status and nutritional deficiencies; and (v) medication and vitamin and mineral supplementation.

RESULTS

One hundred-and-ninety-one children were included with a median age of 19 months (interquartile range 4-63]. Seventeen percent (33/191) were on AAFs and 83% (158/191) were on EHFs. The feeds were commonly used in cancer for 26% and in critical illness for 31%. The majority (73%) of children had enteral feeds via a nasogastric tube. Nutritional biomarkers were performed in 29% of children and 83% were on a vitamin or mineral supplement.

CONCLUSIONS

This practice survey found that EHFs and AAFs were used in a variety of medical conditions. Indications for feed choice varied, and evidence-based research supporting the use was scarce. Awaiting further research, children on these types of feeds should have regular nutritional monitoring.

The efficacy of sacral neuromodulation in the treatment of low anterior resection syndrome: a systematic review and meta-analysis

BACKGROUND

Sacral neuromodulation (SNM) has become one of the main treatment options in patients with fecal incontinence. The aim of this study was to determine the efficacy of sacral neuromodulation in the treatment of low anterior resection syndrome (LARS).

METHODS

A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. The search was conducted using the Pubmed, Embase, Ovid, and Cochrane databases, restricted to the English language and to articles published from 2000 to November 2018.

RESULTS

A total of 434 articles on the efficacy of SNM in the treatment of LARS were retrieved, and 13 studies were included in the final analysis, with a total of 114 patients treated with SNM for LARS The overall success rate excluding study heterogeneity was 83.30% [95% CI (71.33-95.25%)]. Improvement in anal continence was seen in several clinical and functional parameters, including the Wexner Score [10.78 points, 95% CI (8.55-13.02), p < 0.0001], manometric maximum resting pressure [mean improvement of 6.37 mm/Hg, 95% CI (2.67-10.07), p = 0.0007], maximum squeeze pressure [mean improvement of 17.99 mm/Hg, 95% CI (17.42-18.56), p < 0.0001] and maximum tolerated volume [mean improvement of 22.74 ml, 95% CI (10.65-34.83), p = 0.0002]. Quality of life questionnaires also demonstrated significant improvement in patients' quality of life, but were reported only in a small group of included patients.

CONCLUSIONS

SNM significantly improves symptoms and quality of life in patients suffering from fecal incontinence following low anterior resection.

IUPAC Collaborative Trial Study of a Method To Detect Genetically Modified Soy Beans and Maize in Dried Powder

This paper presents results of a collaborative trial study (IUPAC project No. 650/93/97) involving 29 laboratories in 13 countries applying a method for detecting genetically modified organisms (GMOs) in food. The method is based on using the polymerase chain reaction to determine the 35S promoter and the NOS terminator for detection of GMOs. Reference materials were produced that were derived from genetically modified soy beans and maize. Correct identification of samples containing 2% GMOs is achievable for both soy beans and maize. For samples containing 0.5% genetically modified soy beans, analysis of the 35S promoter resulted also in a 100% correct classification. However, 3 false-negative results (out of 105 samples analyzed) were reported for analysis of the NOS terminator, which is due to the lower sensitivity of this method. Because of the bigger genomic DNA of maize, the probability of encountering false-negative results for samples containing 0.5% GMOs is greater for maize than for soy beans. For blank samples (0% GMO), only 2 false-positive results for soy beans and one for maize were reported. These results appeared as very weak signals and were most probably due to contamination of laboratory equipment.

Low-tidal-volume prevent ventilation induced inflammation in a mouse model of sepsis

BACKGROUND AND GOAL OF THE STUDY

Pulmonary inflammation, increased vascular permeability, and pulmonary edema, occur in response to primary pulmonary infections like pneumonia but are also evident in endotoxemia or sepsis. Mechanical ventilation augments pre-existing lung injury and inflammation resulting from exposure to microbial products. The objective of this study was to test the hypothesis that low-tidal-volume prevent ventilation induced lung injury in sepsis.

MATERIALS AND METHODS

10-12-week-old male C57BL/6N-mice received an intraperitoneal (i.p.) injection with equipotent dosages of LPS, 1668-thioate, 1612-thioate, or PBS. 120 min after injection, mice were randomized to low- (LV, 7 ± 1 ml/kg) or high-tidal-volume (HV, 25 ± 1 ml/kg) ventilation. Hemodynamic and ventilatory parameters were recorded and inflammatory markers were analyzed form BAL that was generated after 90 minute ventilation.

RESULTS AND DISCUSSION

Arterial blood pressures declined during mechanical ventilation in all groups. pO₂ decreased in LPS injected and CO₂ increased in sham, LPS, and 1612-thioate administered mice at 45 min and in 1668-thioate injected mice after 90 minute LV ventilation compared to respective HV groups. BAL protein concentrations increased in HV ventilated and 1668- or 1612-thioat pre-treated mice. BAL TNF-α protein concentrations increased in both LPS- and 1668-thioate-injected and IL-1β protein concentrations only in LPS-injected and HV ventilated mice. Most notably, no increased protein concentrations were observed in any of the LV ventilated groups.

CONCLUSION

We conclude that low-tidal-volume ventilation may be a potential strategy for the prevention of ventilator induced lung injury in a murine model of systemic TLR agonist induced lung injury.

Scalable 30 fs laser source with 530 W average power

We present a power-scalable laser source with 30 fs pulse duration, 530 W average power at 500 kHz repetition rate, and beam quality M²<1.2. The compact and efficient setup consists of ytterbium-based Innoslab amplifiers and subsequent nonlinear pulse compression with an argon-filled Herriott cell.

Biallelic CSGALNACT1-mutations cause a mild skeletal dysplasia

Genetic causes of skeletal disorders are manifold and affect, among others, enzymes of bone and connective tissue synthesis pathways. We present a twelve-year-old boy with a mild skeletal dysplasia, hypermobility of joints and axial malalignment of lower limbs and feet. Exome sequencing revealed a biallelic loss of function mutation in CSGALNACT1, which encodes chondroitin sulfate N-acetylgalactosaminyltransferase 1 and plays a major role in the chondroitin sulfate chain biosynthesis and therefore in the synthesis of glycosaminoglycans. Recently, the first case of a pediatric patient with a mild skeletal dysplasia due to a compound heterozygous large intragenic deletion and a damaging missense variant in CSGALNACT1 was reported. We here identify a second case and the first juvenile patient with a homozygous frameshift variant in CSGALNACT1 which corroborates its role in mild and non-progressive skeletal dysplasia with joint laxity.

[Rational use of genetic tests in internal medicine : Possibilities and limitations of next generation sequencing diagnostics]

BACKGROUND

New methods of molecular genetic diagnostics enable a more comprehensive genetic analysis of patients.

OBJECTIVES

Rational use and benefits of molecular genetic testing in patients with various internal diseases.

METHOD

Evaluation of topic-related literature, discussion of own experiences, as well as consideration of current guidelines.

RESULTS

New genetic tests, such as next generation sequencing (NGS), improve the diagnosis of hereditary diseases; however, the use of this technology also leads to additional findings, which must be carefully considered.

CONCLUSION

The rational use of genetic tests is a benefit for patients and can significantly influence the prevention and treatment of a disease. The increasing complexity of genetic findings requires interdisciplinary approaches involving human genetics, internal medicine, and other disciplines.

Seroprevalence of antibodies against bacterial pathogens in sheep from Equatorial Guinea

Equatorial Guinea (EG) is a country in Central Africa with typical tropical weather. Sheep are an important source of food in EG, but the absence of information regarding infectious diseases that affect the native flocks of small ruminants is a concern. The country is currently implementing several new practices in the sheep industry associated with the importation of sheep from other countries. This study aimed to evaluate the seroprevalence of bacterial infections that are important to the sheep industry in EG sheep flocks. The detection of specific antibodies for the four agents studied was performed using enzyme-linked immunosorbent assay in 1,002 serum samples from EG sheep. The results showed a true prevalence of 13.37% for antibodies against Corynebacterium pseudotuberculosis, 0.59% for Brucella ovis, 19.89% for Chlamydophila abortus and 0.79% for Mycoplasma agalactiae in animals from production flocks. Among a group of 35 samples from isolated native animals, 47.56% were seropositive for antibodies against C. pseudotuberculosis, 42.84% for B. ovis, 54.28% for C. abortus and 11.35% for M. agalactiae. These results comprise the first report of the prevalence of infectious diseases in sheep in EG. They highlight the importance of adopting adequate measures to prevent infection by bacteria endemic to EG native flocks during the development of the sheep industry in the country.

Single shot femtosecond laser nano-ablation of CVD monolayer graphene

We investigate ablation of CVD monolayer graphene by femtosecond pulses in the single shot regime. We show that the ablation probability of flat graphene drastically reduces for small illumination diameters even if the ablation threshold is exceeded. However, the presence of graphene wrinkles enhances the ablation probability. This is interpreted in terms of electron and energy diffusion within the graphene layer. This differentiated behavior is a drawback for single shot laser nanopatterning. The morphology of the holes with minimal diameter depends on the fluence distribution at ablation threshold. Strong fluence gradients due to strong focussing produce an explosive folding of graphene during ablation.

Neurodevelopmental outcome of fetal isolated ventricular asymmetry without dilation: a cohort study

OBJECTIVE

Fetal isolated ventricular asymmetry (IVA) is a relatively common finding in pregnancy, but data regarding its effect on neurodevelopmental outcome are scarce and founded principally on ultrasound-based studies. The purpose of this study was to assess the neurodevelopmental outcome of IVA cases in a magnetic resonance imaging (MRI)-based study.

METHODS

Cases referred for fetal brain MRI as part of the assessment of IVA without ventriculomegaly (lateral ventricular atrial diameter ≤ 10 mm), identified during routine ultrasound examination, were assessed for possible inclusion. Asymmetry was defined as a difference in width of ≥ 2 mm between the two lateral ventricles. Forty-three cases were included in the study group and compared with a control group of 94 normal cases without IVA. Children were assessed at ages 13-74 months using the Vineland-II Adaptive Behavior Scales (VABS-II).

RESULTS

VABS-II scores were within normal range. There was no significant difference in composite VABS-II score between the study and control groups (106.5 vs 108.0; P = 0.454). VABS-II scores did not differ between the groups when matched for gender and age at VABS-II interview (109.6 in study group vs 107.8 in control group; P = 0.690).

CONCLUSION

In cases of IVA without ventriculomegaly on MRI, neurodevelopmental test scores were normal and did not differ from cases without IVA. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Boundary spanning at the science-policy interface: the practitioners' perspectives

Cultivating a more dynamic relationship between science and policy is essential for responding to complex social challenges such as sustainability. One approach to doing so is to "span the boundaries" between science and decision making and create a more comprehensive and inclusive knowledge exchange process. The exact definition and role of boundary spanning, however, can be nebulous. Indeed, boundary spanning often gets conflated and confused with other approaches to connecting science and policy, such as science communication, applied science, and advocacy, which can hinder progress in the field of boundary spanning. To help overcome this, in this perspective, we present the outcomes from a recent workshop of boundary-spanning practitioners gathered to (1) articulate a definition of what it means to work at this interface ("boundary spanning") and the types of activities it encompasses; (2) present a value proposition of these efforts to build better relationships between science and policy; and (3) identify opportunities to more effectively mainstream boundary-spanning activities. Drawing on our collective experiences, we suggest that boundary spanning has the potential to increase the efficiency by which useful research is produced, foster the capacity to absorb new evidence and perspectives into sustainability decision-making, enhance research relevance for societal challenges, and open new policy windows. We provide examples from our work that illustrate this potential. By offering these propositions for the value of boundary spanning, we hope to encourage a more robust discussion of how to achieve evidence-informed decision-making for sustainability.

Endothelialization of PTFE vascular grafts under flow induces significant cell changes

Background

To minimize thrombogeneity of small diameter PTFE grafts they are usually coated in vitro with endothelial cells under static culture conditions. The disadvantage of this technique is that a cell layer is formed that fails to withstand shear stress typical in normal blood flow.

Method

Since the in vivo functional and structural status of endothelial cells correlates with the applied shear stress, we developed a computer-controlled perfusion system to seed and culture cells on PTFE-grafts up to a confluent monolayer under the influence of increasing shear stress. The confluence of endothelial coating was defined by immunohistological staining of cross sections, and by upper light microscopy of flattened graft samples. In addition, the expression of fibronectin as an important adhesion molecule was estimated.

Results and discussion

The application of pulsatile shear stress (6.6 dyn/cm2, 5 min) to grafts endothelialized under perfusion (n = 7) did not lead to a disruption of the confluent cell layer. In contrast, a 5 min long shear stress of 3 dyn/cm2was sufficient to wash more than 50% of cells off the PTFE-graft cultured under static conditions (n = 6). The perfusion cultures showed a significantly higher proliferation rate in comparison with static cultures. This effect was reproducibile in both serum-containing and serum-free culture media. The expression of fibronectin by endothelial cells was significantly higher in the perfused graft compared to the static one. These results suggest the practicability of endothelialized PTFE vascular grafts, preconditioned to shear rates similar to the in vivo situation, as an alternative bypass material in cardiac surgery.

Different Types of Aortic Stenosis and Simulation of their Morphological-Hydrodynamic Interdependence - in Vitro Study with Allografts and Stenotic Valve Models

Biological valves display a dependence of valve resistance and valve area on flow and a phase shift between systolic flow through the valves and pressure difference across the valves. The pressure-flow relations of stenosed valves raise questions about the “best measure of stenosis”. There is a need for quantitative evaluation of the hydrodynamic performance of homografts and allografts. In the present paper, we report on in vitro studies of the hydrodynamic behavior of homografts from human donors, allografts from different animal species as well as three valve models. Valve model I was designed to simulate flow-dependence of valve area, valve model II was designed to simulate restricted valve opening independent of flow, and valve model III was designed to simulate a flow-dependent movement of valve root in flow direction. Among other aspects, the effect of increased viscosity of the test fluid on the pressure difference and the effects of water absorption by valve tissue on valve characteristics were investigated. The results of the present studies clearly indicate that any biological valve may be modelled as a serial connection of a model I type valve and a model II type valve. From the results, the dependence of the characteristic pressure-flow relationship of a valve on valve size and valve distensibility can be clearly seen and the clinical significance of the characteristic coefficients of the pressure-flow relationship of a valve can be elucidated. Further, it was shown that the characteristic phase shift between flow and pressure difference displayed by biological valves is due to their movable valve plane similar to that of valve model III.

Simultaneous quantitative susceptibility mapping and Flutemetamol-PET suggests local correlation of iron and β-amyloid as an indicator of cognitive performance at high age

The accumulation of β-amyloid plaques is a hallmark of Alzheimer's disease (AD), and recently published data suggest that increased brain iron burden may reflect pathologies that synergistically contribute to the development of cognitive dysfunction. While preclinical disease stages are considered most promising for therapeutic intervention, the link between emerging AD-pathology and earliest clinical symptoms remains largely unclear. In the current study we therefore investigated local correlations between iron and β-amyloid plaques, and their possible association with cognitive performance in healthy older adults. 116 older adults (mean age 75 ± 7.4 years) received neuropsychological testing to calculate a composite cognitive score of performance in episodic memory, executive functioning, attention, language and communication. All participants were scanned on a combined PET-MRI instrument and were administered T1-sequences for anatomical mapping, quantitative susceptibility mapping (QSM) for assessing iron, and 18F-Flutemetamol-PET for estimating β-amyloid plaque load. Biological parametric mapping (BPM) was used to generate masks indicating voxels with significant (p < 0.05) correlation between susceptibility and 18F-Flutemetamol-SUVR. We found a bilateral pattern of clusters characterized by a statistical relationship between magnetic susceptibility and 18F-Flutemetamol-SUVR, indicating local correlations between iron and β-amyloid plaque deposition. For two bilateral clusters, located in the frontal and temporal cortex, significant relationships (p<0.05) between local β-amyloid and the composite cognitive performance score could be observed. No relationship between whole-cortex β-amyloid plaque load and cognitive performance was observable. Our data suggest that the local correlation of β-amyloid plaque load and iron deposition may provide relevant information regarding cognitive performance of healthy older adults. Further studies are needed to clarify pathological correlates of the local interaction of β-amyloid, iron and other causes of altered magnetic susceptibility.

Clinical Data Mining: a Review

Objective Clinical data mining is the application of data mining techniques using clinical data. We review the literature in order to provide a general overview by identifying the status-of-practice and the challenges ahead.

Methods The nine data mining steps proposed by Fayyad in 1996 [4] were used as the main themes of the review. MEDLINE was used as primary source and 84 papers were retained based on our inclusion criteria.

Results Clinical data mining has three objectives: understanding the clinical data, assist healthcare professionals, and develop a data analysis methodology suitable for medical data. Classification is the most frequently used data mining function with a predominance of the implementation of Bayesian classifiers, neural networks, and SVMs (Support Vector Machines). A myriad of quantitative performance measures were proposed with a predominance of accuracy, sensitivity, specificity, and ROC curves. The latter are usually associated with qualitative evaluation.

Conclusion Clinical data mining respects its commitment to extracting new and previously unknown knowledge from clinical databases. More efforts are still needed to obtain a wider acceptance from the healthcare professionals and for generalization of the knowledge and reproducibility of its extraction process: better description of variables, systematic report of algorithm parameters including the method to obtain them, use of easy-to-understand models and comparisons of the efficiency of clinical data mining with traditional statistical analyses. More and more data will be available for data miners and they have to develop new methodologies and infrastructures to analyze the increasingly complex medical data.

Soluble adenylyl cyclase: A novel player in cardiac hypertrophy induced by isoprenaline or pressure overload

Aims

In contrast to the membrane bound adenylyl cyclases, the soluble adenylyl cyclase (sAC) is activated by bicarbonate and divalent ions including calcium. sAC is located in the cytosol, nuclei and mitochondria of several tissues including cardiac muscle. However, its role in cardiac pathology is poorly understood. Here we investigate whether sAC is involved in hypertrophic growth using two different model systems.

Methods and results

In isolated adult rat cardiomyocytes hypertrophy was induced by 24 h β₁-adrenoceptor stimulation using isoprenaline (ISO) and a β₂-adrenoceptor antagonist (ICI118,551). To monitor hypertrophy cell size along with RNA/DNA- and protein/DNA ratios as well as the expression level of α-skeletal actin were analyzed. sAC activity was suppressed either by treatment with its specific inhibitor KH7 or by knockdown. Both pharmacological inhibition and knockdown blunted hypertrophic growth and reduced expression levels of α-skeletal actin in ISO/ICI treated rat cardiomyocytes. To analyze the underlying cellular mechanism expression levels of phosphorylated CREB, B-Raf and Erk1/2 were examined by western blot. The results suggest the involvement of B-Raf, but not of Erk or CREB in the pro-hypertrophic action of sAC. In wild type and sAC knockout mice pressure overload was induced by transverse aortic constriction. Hemodynamics, heart weight and the expression level of the atrial natriuretic peptide were analyzed. In accordance, transverse aortic constriction failed to induce hypertrophy in sAC knockout mice. Mechanistic analysis revealed a potential role of Erk1/2 in TAC-induced hypertrophy.

Conclusion

Soluble adenylyl cyclase might be a new pivotal player in the cardiac hypertrophic response either to long-term β₁-adrenoceptor stimulation or to pressure overload.

Single-shot ultrafast laser processing of high-aspect-ratio nanochannels using elliptical Bessel beams

Ultrafast lasers have revolutionized material processing, opening a wealth of new applications in many areas of science. A recent technology that allows the cleaving of transparent materials via non-ablative processes is based on focusing and translating a high-intensity laser beam within a material to induce a well-defined internal stress plane. This then enables material separation without debris generation. Here, we use a non-diffracting beam engineered to have a transverse elliptical spatial profile to generate high-aspect-ratio elliptical channels in glass of a dimension 350  nm×710  nm and subsequent cleaved surface uniformity at the sub-micron level.

Nitric oxide and immune response in infection control of Caseous Lymphadenitis

ABSTRACT This study aimed to evaluate aspects of host immune response using an experimental infection model of Corynebacterium pseudotuberculosis (CP) in C57/Black6 wild-type and knockout for nitric oxide (KO-NO) mice. 28 mice were evaluated: 4 wild-type controls; 10 wild-type infected with CP; 4 KO-NO controls; 10 KO-NO infected with CP. Infection procedures were carried out by intraperitoneal inoculation using 107. Infected C57/Black6 KO-NO mice began to die after the 5° day post-inoculation, up until the 14º day. Neutrophils were found in increased numbers in the infiltrate of KO-NO murine peritoneal cavities. Examination of splenic tissue revealed an accumulation of lymphocytes, predominantly CD8 T-cells, in experimental animal groups. KO-NO animals were found to have a predominance of granulomas 7 days post-inoculation, primarily in the lymph nodes. In addition, greater amounts of bacteria were recovered from the mesenteric lymph nodes of KO-NO mice. There was no statistically significant difference in the levels of total IgG and its subclasses 14 days post-inoculation between KO-NO and wild groups. The results suggest the importance of nitric oxide in the process of controlling CP infection, as KO-NO animals were observed to be markedly more affected by infection with this bacterium.

Parental perception of their child's quality of life in children with non-immunoglobulin-E-mediated gastrointestinal allergies

BACKGROUND

Food allergy can have a significant impact on health-related quality of life (HRQoL). Parental proxy questionnaires are commonly used when children are too young to complete questionnaires themselves. Little data are available on HRQoL in children with non-IgE-mediated gastrointestinal food allergy (GIFA). The aim of this study was to evaluate HRQoL in these children by parent proxy.

METHODS

A cross-sectional questionnaire study was conducted with children aged 2-16 years with confirmed GIFA. Parents of these children completed the Pediatric Quality of Life Inventory (PedsQL^™ ) and the family impact module of the PedsQL. The PedsQL scores were compared to two published cohorts: functional abdominal pain (FAP) and IgE-mediated food allergy.

RESULTS

Fifty-two parents of children with GIFA completed the PedsQL^™ parent proxy. The GIFA cohort had significantly better overall HRQoL compared with the FAP cohort, but lower emotional functioning scores. The GIFA cohort also had poorer physical QoL compared with the IgE cohort (all p < 0.05). The more foods excluded, comorbidity of nasal congestion, abdominal pain, back arching, the persistence of flatus and gastrointestinal symptom severity after elimination diet were related to poorer QoL in this non-IgE cohort. Regression analyses showed that number of foods and nasal congestion significantly predicted total QoL score as perceived by parents.

CONCLUSIONS

This study has shown that different areas of HRQoL of children with GIFA are affected compared with children with FAP or IgE-mediated food allergy, highlighting the need for a specific GIFA HRQoL questionnaire to better understand the impact on these children.

High speed cleaving of crystals with ultrafast Bessel beams

We develop a novel concept for ultra-high speed cleaving of crystalline materials with femtosecond lasers. Using Bessel beams in single shot, fracture planes can be induced nearly all along the Bessel zone in sapphire. For the first time, we show that only for a pulse duration below 650 fs, a single fracture can be induced in sapphire, while above this duration, cracks appear in all crystallographic orientations. We determine the influential parameters which are polarization direction, crystallographic axes and scanning direction. This is applied to cleave sapphire with a spacing as high as 25 μm between laser impacts.

Antiepileptic Drugs Impair Shortening of Isolated Cardiomyocytes

Background

Most antiepileptic drugs (AEDs) inhibit seizure generation by acting on voltage-dependent ion channels. Voltage-dependent sodium and calcium channels are commonly expressed in brain and heart, suggesting that AEDs may have considerable cardiodepressive effects, thereby facilitating sudden cardiac death as a potential cause of sudden unexpected death in epilepsy. Here, we investigated the effects of carbamazepine (CBZ), lamotrigine (LTG), and levetiracetam (LEV) alone and in combination on the shortening properties of isolated ventricular cardiomyocytes of wild-type mice.

Methods

Properties of murine cardiomyocytes were determined by recording the sarcomere shortening with a video imaging system before, during, and after administration of AEDs in different concentrations and combinations. We assessed (i) the number of successful shortenings during continuous electrical stimulation (electromechanical coupling) and (ii) the shortening amplitude as well as other shortening-related properties upon repetitive electrical stimulation at 4 Hz. Data are given as mean ± SEM.

Results

At 100 μM, CBZ (10 cells), LTG (11 cells), and LEV (11 cells) alone had no effect on the electromechanical coupling but reversibly reduced shortening amplitudes by 15 ± 4, 24 ± 3, and 11 ± 3%, respectively. Increasing the LTG concentration to 250 (21 cells) and 500 μM (4 cells) reversibly inhibited the electromechanical coupling in 62 and 100% of the experiments. Importantly, simultaneous application of CBZ, LTG, and LEV at 100 μM also impaired the electromechanical coupling in 8 of 19 cardiomyocytes (42%) and reduced the shortening amplitude by 21 ± 4%.

Conclusion

Our data show that AEDs reversibly impair cardiac excitation and contraction. Importantly, the blocking effect on electromechanical coupling appears to be additive when different AEDs are simultaneously applied. The translational value of these experimental findings into clinical practice is limited. Our results, however, suggest that rationale AED therapy may be important with respect to cardiac side effects and potential facilitation of serious cardiac dysfunction especially when AEDs are used in combination or at very high doses.